SEBASTIAN — Rosco is 1 year old, weighs 13 pounds and survived almost a month on his own, away from his family’s home.

The Dachshund is safe at home now, because of a microchip implant and a concerned stranger who spotted the pup and followed him until he could catch him.

“We searched the neighborhood, posted hundreds of flyers and were offering reward money, but when so much time passes you just don’t think you’re going to find them,” Toni Leopold, 73, said.

Rosco escaped June 19 through a hole in a fence with his “big brother,” a 7-year-old, 80-pound mutt. Leopold left her front door and gate open, hoping they would find their way home, but Rosco’s brother wandered back the next morning without him.

Sebastian resident Craig Dubois, 35, found Rosco more than three weeks later in a vacant lot next to an Advance Auto Parts on Highway 512, only feet away from the busy road.

“I saw his head pop up from the knee-high grass and disappear again,” Dubois said. “He looked rough, his eyes closed shut with gunk and a scrape on his side. He was scared and nervous.”

Dubois followed Rosco to a nearby tree where a patch of grass was matted down, like the dog had been there for a while, he said. Little did Rosco know that he was only yards away from his neighborhood behind the Advance Auto Parts at 9240 Sebastian Blvd.

Dubois coaxed Rosco with a hot dog, which he didn’t eat quickly because he was so weak, Dubois said. He wrapped the dog in a blanket and took him to Highlands Animal Hospital, the closest he could find.

There, Leopold had pinned a lost dog flyer to the vet’s bulletin board weeks earlier.

“Sure enough there was Rosco’s picture, but we couldn’t be 100 percent sure,” Dubois said. “We were about to go ahead and pay for his checkup when the vet discovered he was microchipped.”

Veterinarian Marcus Kramer used the microchip’s registered information to reunite Rosco with the Leopolds. He noted some wounds and weighed Rosco at only 10 pounds — a 5-pound loss from his checkup in May. He may have also contracted ring worm, but is being treated with antibiotics.

“He had lesions all over and (the hair around) his eyes was so matted he could barely open them,” Kramer said.

Rosco has since been groomed, gained 3 pounds and is recovering from his cuts and scrapes.

“We’re just happy to have him home when we had just about given up,” Leopold said.

Microchip your pet

What: Bioglass microchip that puts off a radio frequency with an ID number that can be picked up by a chip scanner.

How: Owners can have their pets microchipped at their veterinary clinics and register ID information online with the microchip company. Information can be accessed by a chip scanner at most animal shelters, veterinary clinics and hospitals.